Direct Noise Simulation of Near Field Noise during a Gas Injection Process with a Discontinuous Galerkin Approach

Abstract

In this paper, we present results on the noise radiated by a supersonic gas jet through a gas injection nozzle which is commonly used in cars powered by compressed natural gas. Direct aeroacoustic simulation results, provided by a discontinuous Galerkin solver for the unsteady compressible Navier Stokes equations, are presented. Due to its local formulation with high order accuracy and low dissipation and dispersion, it is well suited for both flow resolution and wave propagation. The discontinuous Galerkin scheme preserves these properties even on unstructured hybrid grids, allowing to mesh the complex threedimensional geometries. The scheme is fully parallelized and simulations are run on 2048 cores. We show that the sound radiation can be adequately predicted and that sound pressure level spectra are in good agreement with experimental data.

Analyzing the Effect and Performance of Lossy Compression on Aeroacoustic Simulation of Gas Injector

“…The surface mesh of the external injector is shown in Figure 4b. For a more detailed description of the geometry and the boundaries we refer to Kraus et al [33]. The simulation is in excellent agreement with experiential data from [34].…”

“…The reference pressure is usually taken to be 20 micro pascals. For analyzing the effect of lossy compression on SPLs we have followed the simulation set-up proposed by [33,34], which has been shown to reproduce experimental data very accurately.…”